With rapid development in User Equipments (UEs), the UEs are capable of operating in multi-access priority mode, with a wide variety of applications or services such as internet service, networked gaming, voice call service along with Machine Type Communication (MTC) applications each having different levels of priority and resource requirements. For example, some applications on these UEs such as voice call have normal priority, while applications such as MTC may have low priority for network access. Rise in demand for communication of large amounts of data to and from the UE are bound to overload the network and cause congestion in the communication network.
To address network overload and congestion issues that lead to excessive access attempts to a network, 3GPP specifies various mechanisms at various network levels such as rejecting connection requests based on UE priority, implementing Access Class barring (ACB) mechanism, Extended Access Barring (EAB) mechanism and so on. The Radio Resource Control (RRC) and Non Access stratum (NAS) connection request rejection mechanism provides a rejection message along with the rejection cause and a back-off time to the UE. Then the UE tries to re-attempt only after the back-off timer initiated by the UE expires. The EAB mechanism provides congestion control by barring the EAB configured UE's from accessing the network during network overloads and allowing re-attempts at a later instant of time when the EAB is alleviated by the network similar to ACB.
However, in accordance with current 3GPP standards, access barring mechanism or the RRC connection rejection mechanism specified applies to the UE as whole. Existing methods specified in 3GPP specification fail to apply congestion control individually to every application or specific application on the UE. Today the UE behavior is at a device level, i.e. when the network specifies a barring, it typically applies to all applications on that UE. Ideally for a UE supporting multiple applications each application should have a different priority level for accessing the network. For example, if the network applies EAB for low priority access, then existing methods bar the UE to access the network even for other normal priority applications on the UE that request service. Further the UE is “always on” in the packet switched network (LTE) and make these access controls (ACB/EAB) inefficient, as these access control mechanisms are only applicable to the UE in the Idle state. These requirements are intended to mitigate overload of the access network and/or core network under situation defined by operators, e.g. in heavy congestion or disaster case. There exists no mechanism for UEs that are in connected mode.
In the existing mechanisms, the ACB/EAB mechanism does not apply for UEs that are in the connected mode DRX (Discontinuous Reception mode) and there exists no mechanism to apply any barring mechanism to UEs that are already in connected mode. The UE could still continue Random Access Channel (RACH) message or Buffer Status Report (BSR) message and Scheduling Request (SR) messages to a network and get service, there is no way to stop a UE from sending service request once it is in a connected mode. It has to be noted that today almost all UEs continue to stay in connected mode for extended periods of time and as such there will be no mechanism left with a network to bar users when the network is congested.
In the light of above discussion, a method and system that defines a mechanism to have independent application granular network access control for the UE in the connected state and also in idle state is required.